JP5906442B2 - Lens barrel and imaging device - Google Patents

Description

  The present disclosure relates to a retractable lens barrel.

  In the lens barrels disclosed in Patent Document 1 and Patent Document 2, a rotating frame on which a helicoid is formed is rotated by a zoom motor. Moreover, in this lens barrel, the lens frame is moved in the optical axis direction together with the rotation frame by restricting the rotation of the lens frame by the fixed frame. As a result, the focal length is adjusted or the desired main subject is focused.

Japanese Patent Laid-Open No. 5-100144 Japanese Patent Application Laid-Open No. 8-21470

  The present disclosure provides a collapsible lens barrel that can have a longer overall length when used.

The lens barrel according to the present disclosure includes a fixed frame, a rotating frame, a first rectilinear frame, a first lens holding frame, and a first drive unit. The rotating frame engages with the fixed frame. The first rectilinear frame is engaged with the rotating frame. The first lens holding frame holds a first lens group including at least one lens. The first lens holding frame is engaged with the rotating frame. The first drive unit is attached to the first rectilinear frame. The first drive unit drives the rotating frame to rotate around the optical axis.
Here, the first drive unit and the first rectilinear frame move together in the optical axis direction relative to the fixed frame as the rotary frame rotates by driving the first drive unit. At this time, the first lens holding frame further moves in the optical axis direction relative to the first rectilinear frame that moves relatively.

  The retractable lens barrel according to the present disclosure is effective in increasing the overall length of the lens barrel in use.

1 is a perspective view of an imaging apparatus according to a first embodiment. Sectional drawing of the lens-barrel in the retracted state concerning Embodiment 1 Sectional view of the lens barrel in the telephoto end photographing state according to the first embodiment The figure which shows engagement of the cam frame gear and output gear concerning Embodiment 1. FIG. FIG. 3 is an internal perspective view of the lens barrel according to the first embodiment. FIG. 3 is an internal perspective view of the lens barrel according to the first embodiment. FIG. 3 is an internal front view of the lens barrel according to the first embodiment. FIG. 3 is an internal front view of the lens barrel according to the first embodiment. FIG. 3 is an internal front view of the lens barrel according to the first embodiment. Sectional drawing of the lens-barrel in the retracted state concerning Embodiment 2 Sectional drawing of the lens-barrel in the retracted state concerning Embodiment 3

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.
The inventor provides the accompanying drawings and the following description in order for those skilled in the art to fully understand the present disclosure, and is not intended to limit the subject matter described in the claims. Absent.

(Embodiment 1)
FIG. 1 is a perspective view of the imaging apparatus 1 according to the first embodiment. The imaging device 1 is an interchangeable lens digital camera, and mainly includes a camera body 3 and a lens barrel 2 that is detachably attached to the camera body 3. The lens barrel 2 holds a lens 4 (G1, G2, G3, G4 described later). In FIG. 1, the optical axis AX is displayed as the optical axis of the lens 4. The optical axis AX direction is a direction along the optical axis AX, and is a direction parallel to the optical axis AX. The lens barrel 2 includes a zoom lever 77 and a focus lever 78. The zoom lever 77 receives a user operation and adjusts the focal length by driving the lens 4 in the optical axis AX direction. The focus lever 78 receives a user operation and adjusts the focus by driving the lens 4 in the direction of the optical axis AX.

FIG. 2 is a cross-sectional view of the lens barrel 2 in the retracted state according to the first embodiment. The lens barrel 2 includes an outer frame 70, a lens mount 71, a fixed frame 74, a cam frame 50 (an example of a rotating frame ), an inner rectilinear frame 41 (an example of a first rectilinear frame ), and an outer rectilinear frame 46. (An example of the second rectilinear frame ), the first lens group G1, the first lens holding frame 11, the second lens holding frame 15 , the third lens holding frame 17, and the fourth lens holding frame 19. And a zoom motor unit 60 (an example of a first drive unit). The outer frame 70 and the fixed frame 74 are an example of a fixed frame .

The lens mount 71 is a mount that can be attached to the camera body 3. The outer frame 70 is fixed to the lens mount 71 and is a substantially cylindrical member. The fixed frame 74 is fixed to the outer frame 70.
The cam frame 50 includes a second bayonet key 48b provided on the outer peripheral side, a first cam pin 56 , a first bayonet groove 43a provided on the inner peripheral side, and a cam provided closer to the lens mount 71 than the inner rectilinear frame 41. A frame gear 55 (an example of a gear portion) is provided. The first cam pin 56 engages with the outer frame 70. The cam frame 50 is supported so as to be guided in the direction of the optical axis AX relative to the outer frame 70 by rotating around the optical axis AX.

The inner rectilinear frame 41 is provided on the inner peripheral side of the cam frame 50, and includes a second rectilinear key 42 at the end far from the cam frame gear 55 and a first bayonet key 43b on the inner peripheral side. The first bayonet groove 43a engages with the first bayonet key 43b. The inner rectilinear frame 41 is supported so as to be movable in the optical axis AX direction together with the cam frame 50 while the relative movement in the optical axis AX direction with the cam frame 50 is restricted.

The outer rectilinear frame 46 includes a third rectilinear key 47 on the outer peripheral side, a second bayonet groove 48a on the inner peripheral side, and a second rectilinear guide groove 49 extending in the optical axis AX direction on the inner peripheral side. The third rectilinear key 47 engages with the third rectilinear guide groove 72, restricts the rotation of the outer rectilinear frame 46 around the optical axis AX, and supports the outer rectilinear frame 46 movably in the optical axis AX direction. The second bayonet groove 48a engages with the second bayonet key 48b. The outer rectilinear frame 46 is restricted from moving relative to the cam frame 50 in the optical axis AX direction. The outer rectilinear frame 46 is supported so as to be movable in the optical axis AX direction together with the cam frame 50.

The first lens holding frame 11 holds the first lens group G1. The first lens holding frame 11 is held by the outer rectilinear frame 46. The first lens holding frame 11 is disposed between the outer rectilinear frame 46 and the inner rectilinear frame 41 in a direction (radial direction) orthogonal to the optical axis AX.
The first lens holding frame 11 includes a second cam pin 12 (an example of a first cam pin) provided on the inner peripheral side, a first straight guide groove 13 provided on the inner peripheral side, and a first straight advance key provided on the outer peripheral side. 14. The first rectilinear key 14 engages with the second rectilinear guide groove 49 and restricts the rotation of the first lens holding frame 11 around the optical axis AX. The first lens holding frame 11 can be moved in the direction of the optical axis AX by the first straight key 14.

The second lens holding frame 15 holds the second lens group G2. The second lens holding frame 15 includes a third cam pin 16 (an example of a second cam pin) on the outer peripheral side. The third cam pin 16 engages with the inner rectilinear frame 41 in the circumferential direction, and engages with the cam frame 50 outside the inner rectilinear frame 41. Thereby, the second lens holding frame 15 is supported so as to be movable in the optical axis AX direction by the rotation operation of the cam frame 50 while the rotation around the optical axis AX is restricted.

The third lens holding frame 17 holds the third lens group G3. The third lens holding frame 17 includes a fourth cam pin 18 (an example of a third cam pin) on the outer peripheral side. The fourth cam pin 18 engages with the inner rectilinear frame 41 in the circumferential direction, and engages with the cam frame 50 outside the inner rectilinear frame 41. Thereby, the third lens holding frame 17 is supported so as to be movable in the direction of the optical axis AX by the rotation operation of the cam frame 50 while the rotation around the optical axis AX is restricted.

The fourth lens holding frame 19 holds the fourth lens group G4. The fourth lens holding frame 19 includes a fifth cam pin 20 (an example of a fourth cam pin) on the outer peripheral side. The fifth cam pin 20 engages with the inner rectilinear frame 41 in the circumferential direction, and engages with the cam frame 50 outside the inner rectilinear frame 41. Accordingly, the fourth lens holding frame 19 is supported so as to be movable in the direction of the optical axis AX by the rotation operation of the cam frame 50 while the rotation around the optical axis AX is restricted.

The zoom motor unit 60 includes a zoom motor 61 (an example of an actuator), an output shaft 62, a speed reduction unit 63, and an output gear 65. The output shaft 62, a speed reduction unit 63 including a gear train 64 described later, and the output gear 65 are examples of a transmission mechanism.
The cross section of the zoom motor 61 is substantially oval. More specifically, Zumumo motor 61 of the cross section is in a shape cut out in parallel a circle with a straight line, is formed. That is, the cross-sectional portion of the zoom motor 61 is formed from linear portions (H cut portions described later) facing each other and curved portions facing each other.

  The speed reduction unit 63 has a gear train 64. The power of the zoom motor 61 is transmitted to the output gear 65 via a gear train 64 (deceleration unit 63) connected to the output shaft 62. The output gear 65 is engaged with the cam frame gear 55 closer to the lens mount 71 than the inner rectilinear frame 41. The zoom motor unit 60 is attached to the inner peripheral side of the inner rectilinear frame 41. Accordingly, when the output shaft 62 of the zoom motor 61 is rotationally driven, the cam frame 50 is rotationally driven around the optical axis AX via the gear train 64, the output gear 65, and the cam frame gear 55.

The focus lens frame 28 (an example of a fourth lens holding frame ) holds the focus lens 29. The focus lens frame 28 is supported so as to be relatively movable in the optical axis direction with respect to the third lens holding frame 17, and is driven in the optical axis AX direction by a focus motor unit 35 (an example of a second drive unit). .
The aperture unit 66 is attached to the third lens holding frame 17. The aperture unit 66 includes a plurality of aperture blades 67 and an aperture motor 68 that drives the aperture blades 67. The diaphragm blade 67 is driven by the driving force generated by the diaphragm motor 68. The diaphragm blade 67 is configured to be able to adjust the amount of light passing through each lens group by moving forward and backward in the optical path.

The electric board 75 is attached to the fixed frame 74 and is electrically connected to the electric contact unit 76. In the first embodiment, the electric board 75 is disposed on the inner peripheral side of the cam frame 50 when viewed from the optical axis AX direction. Thereby, the cam frame 50 can be brought closer to the lens mount 71, and the lens barrel 2 can be downsized.
In the first embodiment, the case where an optical system having a lens configuration including four lens groups and a focus lens group is realized is illustrated. However, the present invention is not limited to this.

  FIG. 3 is a cross-sectional view of the lens barrel 2 in the telephoto end photographing state according to the first embodiment. The zoom motor unit 60 drives the cam frame 50 to rotate. As a result, the cam frame 50, the inner rectilinear frame 41, and the first lens holding frame 11 move in the optical axis direction. In the lens barrel 2, the first lens holding frame 11 does not overlap with the outer frame 70 when viewed from the direction perpendicular to the optical axis in the telephoto end state where the first lens holding frame 11 is moved to the most object side.

  FIG. 4 is a diagram illustrating engagement between the cam frame gear 55 and the output gear 65 according to the first embodiment. The cam frame gear 55 is arranged so that the mountain diameter RY, that is, the innermost inner diameter of the cam frame gear 55 is the same as the inner diameter of the inner rectilinear frame 41 or larger than the inner diameter of the inner rectilinear frame 41. That is, the cam frame gear 55 is disposed so as not to protrude to the inner peripheral side of the inner rectilinear frame 41. The peak diameter RY is the length of a line segment connecting the optical axis AX and the peak part 55a (top part) of the gear part in the radial direction.

FIG. 5 is a perspective view of the second lens holding frame 15, the third lens holding frame 17, the fourth lens holding frame 19, the zoom motor unit 60, and the electric board 75. The zoom motor 61 is disposed between the third cam pin 16 and the fourth cam pin 18 in the circumferential direction. In the zoom motor 61, the output shaft 62 (rotary shaft) is disposed substantially parallel to the optical axis AX. The deceleration unit 63 is arranged in the circumferential direction. In the deceleration unit 63, the output gear 65 protrudes radially outward. When viewed from the optical axis AX direction, the speed reduction unit 63 and the third cam pin 16 overlap. The electric board 75 is formed in a disk shape with a hole in the center. In the electric board 75, a region where the speed reduction unit 63 is provided is cut out. Thereby, even if the speed reduction unit 63 moves to a position where it overlaps with the electric board 75 when viewed from the direction orthogonal to the optical axis AX direction, interference between the speed reduction unit 63 and the electric board 75 can be prevented. Accordingly, the zoom motor unit 60 can be brought closer to the lens mount 71 when the lens barrel is retracted, and the lens barrel 2 can be downsized.

FIG. 6 is a perspective view showing a state in which the second lens holding frame 15, the third lens holding frame 17, the fourth lens holding frame 19, the zoom motor unit 60, and the electric board 75 are inserted into the inner rectilinear frame 41. The second lens holding frame 15, the third lens holding frame 17, and the fourth lens holding frame 19 are inserted into the inner rectilinear frame 41 from the subject side. At this time, the third cam pin 16 engages with the first through groove 44, and the fourth cam pin 18 and the fifth cam pin 20 provided in the same phase in the circumferential direction engage with the second through groove 45. In the third cam pin 16 and the first through groove 44, the circumferential width (the width in the direction orthogonal to the optical axis AX direction) is substantially the same. Further, in the fourth cam pin 18 , the fifth cam pin 20 , and the second through groove 45, the circumferential width (the width in the direction orthogonal to the optical axis AX direction) is substantially the same. As a result, the second lens holding frame 15, the third lens holding frame 17, and the fourth lens holding frame 19 are restricted from rotating around the optical axis and can move in the optical axis AX direction. The third cam pin 16 , the fourth cam pin 18 , the fifth cam pin 20 , the first through groove 44, and the second through groove 45 are provided at three locations.

  The second rectilinear key 42 is provided at three positions on the end of the inner rectilinear frame 41 on the side far from the cam frame gear 55. The second rectilinear key 42 engages with each of the three first rectilinear guide grooves 13 provided on the inner peripheral side of the first lens holding frame 11. Thereby, the rotation of the inner rectilinear frame 41 around the optical axis AX is restricted. Although the detailed description is omitted, the other rectilinear keys are engaged in the same manner as the other rectilinear guide grooves and their rotation is restricted.

FIG. 7 is an internal front view of the lens barrel 2 as seen from the direction of the optical axis AX. The third cam pin 16 overlaps with the speed reduction unit 63 when viewed from the optical axis AX direction. At least one of the third cam pin 16 and the fourth cam pin 18 is disposed between the zoom motor 61 and the focus motor unit 35 in the circumferential direction. Specifically, at least one of the third cam pin 16 and the fourth cam pin 18 is disposed in a range where the distance between the zoom motor 61 and the focus motor unit 35 is short in the circumferential direction.

  FIG. 8 is an internal front view of the lens barrel 2 as seen from the optical axis AX direction. The focus lens frame 28 holds a focus lens 29. The focus lens frame 28 includes a guide part 30 and a rotation restricting part 31. The focus lens frame 28 engages with a focus guide shaft 32 provided on the third lens holding frame 17 and a focus rotation restriction shaft 33. The focus lens frame 28 is supported by the focus guide shaft 32 so as to be movable in the optical axis AX direction, and the rotation around the focus guide shaft 32 is restricted by the focus rotation restriction shaft 33. The focus motor unit 35 includes a focus motor 36, a screw 37 on which a screw is formed, and a sheet metal 38. The focus motor unit 35 is attached to the third lens holding frame 17. When the screw 37 is rotationally driven by the focus motor 36, the rack 34 engaged with the screw 37 is driven in the optical axis AX direction. As a result, the focus lens frame 28 is driven integrally with the rack 34 in the direction of the optical axis AX.

FIG. 9 is an internal front view of the lens barrel 2 as seen from the optical axis AX direction. The zoom motor 61 has, for example, a shape obtained by H-cutting a cylinder. The H cut portion of the zoom motor 61 is arranged in the normal direction of the lens barrel 2. The zoom motor 61 is provided outside the aperture unit 66 in the radial direction. On the other hand, the deceleration unit 63 and the aperture unit 66 partially overlap when viewed from the optical axis AX direction. The focus motor 36 has a rotational axis arranged substantially parallel to the optical axis AX. The focus motor 36 is disposed between the third cam pin 16 and the fourth cam pin 18 in the circumferential direction. Specifically, the focus motor 36 is disposed in a range where the distance between the third cam pin 16 and the fourth cam pin 18 is short in the circumferential direction. Further, the third cam pin 16 and the fourth cam pin 18 are arranged in a range where the distance between the zoom motor 61 and the focus motor unit 35 is short in the circumferential direction. Further, the deceleration unit 63 and the third cam pin 16 partially overlap when viewed from the optical axis AX direction.

  In the present embodiment, the lens barrel 2 includes a fixed frame 74, a cam frame 50, an inner rectilinear frame 41, a first lens group G1, a first lens holding frame 11, and a zoom motor unit 60. Prepare. The cam frame 50 is supported by the fixed frame 74 so as to be rotatable around the optical axis and to be movable in the optical axis direction. The inner rectilinear frame 41 moves in the optical axis direction while maintaining a constant distance from the cam frame 50 in the optical axis direction. That is, the inner rectilinear frame 41 moves in the optical axis direction together with the cam frame 50. The first lens group G1 is a lens that receives the light of the subject. The first lens group G1 includes at least one lens. The first lens holding frame 11 holds the first lens group, engages with the cam frame 50, and is supported by the outer rectilinear frame 46 so as to be movable in the optical axis direction. The zoom motor unit 60 is attached to the inner rectilinear frame 41 and drives the cam frame 50 to rotate. The cam frame 50, the inner rectilinear frame 41, and the first lens holding frame 11 are movable relative to the fixed frame 74 in the optical axis direction. When viewed from the direction perpendicular to the optical axis, the first lens holding frame 11 does not overlap with the fixed frame 74 when moved to the most object side.

  Thereby, even if the cam frame 50 moves in the optical axis AX direction, the zoom motor 61 can always transmit the rotational driving force to the cam frame 50. The amount of movement of the first lens holding frame 11 in the optical axis AX direction is the sum of the amount of movement of the cam frame 50 relative to the fixed frame 74 and the amount of movement of the first lens holding frame 11 relative to the cam frame 50. Thereby, even if the retractable length is small, the amount of movement of the first lens group G1 in the optical axis AX direction can be increased. Therefore, the entire length of the lens barrel during use can be made longer.

In the lens barrel 2 of the present embodiment, the zoom motor unit 60 is attached to the inner peripheral side of the inner rectilinear frame 41.
As a result, it is possible to eliminate an extra protrusion as compared with the case where the zoom motor unit 60 is attached to the outside of the lens barrel 2. Therefore, the lens barrel 2 can be reduced in size, and the external shape becomes substantially cylindrical, so that a smarter design can be realized.

In the lens barrel 2 of the present embodiment, the cam frame 50 has a cam frame gear 55. The zoom motor unit 60 includes a zoom motor 61, an output shaft 62, a speed reduction unit 63, a gear train 64, and an output gear 65. The output gear 65 engages with the cam frame gear 55 and transmits the output of the zoom motor 61 to the cam frame 50.
Accordingly, the cam frame 50 can be rotationally driven from the inner peripheral side by the zoom motor 61 and the output of the zoom motor 61 can be amplified by the deceleration unit 63. Therefore, the zoom motor 61 and the lens barrel 2 can be reduced in size, and the outer appearance is also substantially cylindrical, so that a smarter design can be realized.

Further, in the lens barrel 2 of the present embodiment, the crest diameter of the cam frame gear 55 is the same as the inner diameter of the inner rectilinear frame 41 or larger than the inner diameter of the inner rectilinear frame 41.
Thereby, even if the cam frame gear 55 moves in the circumferential direction or the optical axis AX direction, the locus of the cam frame gear 55 does not protrude toward the inner peripheral side of the inner rectilinear frame 41. Therefore, it becomes possible to efficiently arrange components on the inner peripheral side of the inner rectilinear frame 41, and the lens barrel 2 can be downsized.

In the lens barrel 2 of the present embodiment, the longitudinal direction of the zoom motor unit 60 is disposed substantially parallel to the optical axis AX. The longitudinal direction of the zoom motor unit 60 corresponds to the direction in which the output shaft 62 extends.
Accordingly, the diameter of the circumscribed circle of the zoom motor unit 60 around the optical axis AX can be reduced as compared with the case where the longitudinal direction of the zoom motor unit 60 is inclined or orthogonal to the optical axis AX. Therefore, the diameter of the lens barrel 2 can be reduced.

  In the lens barrel 2 of the present embodiment, the shortest dimension direction of the zoom motor unit 60 is arranged in the normal direction of the inner rectilinear frame 41. In other words, the shortest dimension direction of the zoom motor unit 60 is along the radial direction orthogonal to the optical axis AX. In addition, the shortest dimension direction of the zoom motor unit 60 is a direction in which a straight line that is substantially orthogonal to a linear portion that faces the cross section of the zoom motor unit 60 extends. More specifically, in the cross section of the zoom motor 61, when the direction orthogonal to the straight line portion is defined as the short axis direction and the direction orthogonal to the short axis direction is defined as the long axis direction, The shortest dimension direction corresponds to the minor axis direction.

Thereby, the diameter of the circumscribed circle of the zoom motor unit 60 around the optical axis AX can be minimized. Therefore, the diameter of the lens barrel 2 can be reduced.
In the lens barrel 2 of the present embodiment, the end of the cam frame 50 in the optical axis direction has a cam frame convex portion 57 (an example of a protruding portion). The cam frame convex portion 57 protrudes in the optical axis direction from the end portion of the inner rectilinear frame 41 with the end portion of the inner rectilinear frame 41 as a reference. Specifically, the cam frame convex portion 57 protrudes in the optical axis direction from the end portion of the inner rectilinear frame 41 disposed on the same side as the end portion of the cam frame 50 in the optical axis direction. The cam frame gear 55 is provided on the cam frame convex portion 57.

  Accordingly, the output of the zoom motor unit 60 on the inner peripheral side of the inner rectilinear frame 41 can be transmitted to the cam frame 50 on the outer peripheral side of the inner rectilinear frame 41 without the need to cut out the inner rectilinear frame 41. Therefore, the degree of freedom of arrangement of the first bayonet groove 43a and the first bayonet key 43b can be secured, the mechanism for transmitting the output of the zoom motor unit 60 to the cam frame 50 can be downsized, and the lens barrel 2 can be downsized.

  The lens barrel 2 of the present embodiment further includes an outer rectilinear frame 46. The outer rectilinear frame 46 is engaged with the outer frame 70 and is restricted from rotating by the outer frame 70. The outer rectilinear frame 46 engages with the cam frame 50 and is supported so as to be movable in the optical axis direction while maintaining a constant distance from the cam frame 50 in the optical axis direction. The first lens holding frame 11 is engaged with the outer rectilinear frame 46 and is restricted from rotating by the outer rectilinear frame 46. The inner rectilinear frame 41 engages with any one of the first lens holding frame 11, the outer frame 70, and the outer rectilinear frame 46, and the rotation is restricted by any one of the frames.

Accordingly, the rotation of the outer rectilinear frame 46 and the inner rectilinear frame 41 can be restricted, and the first lens holding frame 11, the second lens holding frame 15, the third lens holding frame 17, and the fourth lens holding frame 19 can be restricted. it can. Therefore, each lens group can be extended to the subject side with respect to the outer frame 70, and the entire length of the lens barrel when the lens barrel 2 is used can be made longer.
Further, in the lens barrel 2 of the present embodiment, the cam frame convex portion 57 is provided at the end of the cam frame 50 on the lens mount 71 side.

Thereby, the cam frame gear 55 and the zoom motor unit 60 can be arranged on the side far from the subject. Therefore, the lens barrel 2 can be arranged at a position where the zoom motor unit 60 cannot be seen when the lens barrel 2 is viewed from the subject side, and the lens barrel 2 having a good appearance can be realized.
In the lens barrel 2 of the present embodiment, the inner rectilinear frame 41 is provided on the inner peripheral side of the cam frame 50. The inner rectilinear frame 41 is engaged with the first lens holding frame 11 at the end of the cam frame 50 on the side far from the cam frame gear 55, and the rotation is restricted by the first lens holding frame 11. Here, the end of the cam frame 50 on the side far from the cam frame gear 55 corresponds to the end of the cam frame 50 opposite to the cam frame gear 55, that is, the end on the subject side.

  Accordingly, the inner rectilinear frame 41 and the first lens holding frame can be engaged without hindering the engagement between the zoom motor unit 60 and the cam frame gear 55. Therefore, the rotation restricting configuration of the inner rectilinear frame 41 can be simplified, and the inner rectilinear frame 41 can be restricted even if the first lens holding frame moves to the subject side in the optical axis AX direction relative to the outer frame 70. Can be extended to the subject side with respect to the outer frame 70, and the entire length of the lens barrel when the lens barrel 2 is used can be made longer.

In the lens barrel 2 of the present embodiment, the first lens holding frame 11 is provided on the outer peripheral side of the cam frame 50. At least one of the second cam pin 12 and the first cam groove 51 is provided on the inner peripheral side of the first lens holding frame 11. On the outer peripheral side of the cam frame 50, at least one of the second cam pins 12 and the first cam grooves 51 is provided. The second cam pin 12 and the first cam groove 51 are engaged with each other. The outer rectilinear frame 46 is provided on the outer peripheral side of the first lens holding frame 11.

Thereby, the cam mechanism for driving the first lens holding frame 11 in the optical axis AX direction can be disposed on the inner peripheral side of the first lens holding frame 11 or the inner peripheral side of the outer rectilinear frame 46. Therefore, since the cam mechanism cannot be seen from the outside of the lens barrel 2, the lens barrel 2 having a good appearance can be realized without newly providing external parts.
Further, the lens barrel 2 of the present embodiment further includes a second lens holding frame 15 disposed on the inner peripheral side of the inner rectilinear frame 41. The second lens holding frame 15 has a third cam pin 16 that penetrates the inner rectilinear frame 41 from the inner peripheral side to the outer peripheral side and engages with the cam frame 50. The cam frame 50 has a second cam groove 52 that engages with the third cam pin 16 on the inner peripheral side. The second lens holding frame 15 is restricted in rotation by engagement with the inner rectilinear frame 41 and is driven in the optical axis direction by the rotation of the cam frame 50.

Thus, the plurality of lens groups can be driven in the direction of the optical axis AX, and the cam mechanism and the rotation restricting mechanism can be arranged so as not to be seen from the outside of the lens barrel 2. Therefore, the degree of freedom in optical design and mechanism design is increased, and a smaller lens barrel 2 can be realized.
In the lens barrel 2 of the present embodiment, the second lens holding frame 15 holds the second lens group G2 including at least one lens. The second lens group G2 is provided closer to the lens mount 71 than the first lens group G1.

Thereby, the cam mechanism and the rotation restricting mechanism can be arranged so as not to be seen from the outside of the lens barrel 2. Therefore, the lens barrel 2 having a good appearance can be realized without newly providing external parts.
The lens barrel 2 according to the present embodiment further includes a third lens holding frame 17 disposed on the inner peripheral side of the inner rectilinear frame 41. The third lens holding frame 17 has a fourth cam pin 18 that penetrates the inner rectilinear frame 41 from the inner peripheral side to the outer peripheral side and engages with the cam frame 50. A third cam groove 53 that engages with the fourth cam pin 18 is provided on the inner peripheral side of the cam frame 50. The third lens holding frame 17 is restricted in rotation by engagement with the inner rectilinear frame 41 and is driven in the optical axis direction by the rotation of the cam frame 50. When viewed from the optical axis direction, the zoom motor 61 is disposed between the third cam pin 16 and the fourth cam pin 18 .

Accordingly, a plurality of lens groups can be driven in the optical axis AX direction, the degree of freedom in optical design can be increased, and the zoom motor 61 can be arranged long in the optical axis AX direction. Further, the light from the third cam pin 16 and the fourth cam pin 18 The degree of freedom in arrangement in the axis AX direction can be increased. Therefore, the retractable length of the lens barrel 2 can be further shortened while realizing a high speed drive by disposing a larger zoom motor 61, thereby realizing a reduction in size.

In the lens barrel 2 of the present embodiment, at least one of the third cam pin 16 and the fourth cam pin 18 overlaps with the speed reduction unit 63 when viewed from the optical axis direction.
Thereby, the deceleration unit 63 can be lengthened in the circumferential direction. Therefore, the reduction ratio by the reduction unit 63 can be gained, and the torque of the zoom motor 61 can be increased.

The lens barrel 2 of the present embodiment further includes a focus lens frame 28 and a focus motor unit 35. The focus lens frame 28 is supported to be movable relative to the second lens holding frame 15 in the optical axis direction. The focus motor unit 35 drives the focus lens frame 28 in the optical axis direction. The focus motor unit 35 is disposed between the third cam pin 16 and the fourth cam pin 18 when viewed from the optical axis direction.

As a result, the focus lens frame 28 can be driven in the optical axis AX direction, the degree of freedom in optical design can be increased, and the focus motor unit 35 can be disposed long in the optical axis AX direction. Further, the third cam pin 16 and the fourth cam pin 18 The degree of freedom of arrangement in the optical axis AX direction can be increased. Therefore, the retractable length of the lens barrel 2 can be shortened while increasing the moving distance of the focus lens frame 28 in the direction of the optical axis AX, and downsizing can be realized.

In the lens barrel 2 of the present embodiment, at least one of the third cam pin 16 and the fourth cam pin 18 is disposed between the zoom motor unit 60 and the focus motor unit 35.
Thereby, the 3rd cam pin 16 and the 4th cam pin 18 can be equally arrange | positioned in the state near equal intervals by the circumferential direction. Therefore, the postures of the second lens group G2 and the third lens group G3 can be further stabilized.

Further, the lens barrel 2 of the present embodiment further includes an electric substrate 75. The electric board 75 is attached to the outer frame 70 and supplies electricity to the zoom motor unit 60.
In a state where the inner rectilinear frame 41 is moved most toward the lens mount 71, the zoom motor unit 60 and the electric board 75 are disposed in a plane orthogonal to the optical axis.
Thereby, the zoom motor unit 60 can be disposed closer to the lens mount 71 when retracted. Therefore, the retractable length of the lens barrel 2 can be shortened and the size can be reduced.

  Further, the lens barrel 2 of the present embodiment further includes a diaphragm unit 66 that is arranged to be movable in the optical axis direction with respect to the outer frame 70. The aperture unit 66 adjusts the amount of light taken from the subject. The zoom motor 61 and the aperture unit 66 are arranged side by side in the radial direction. The zoom motor 61 is movable in the optical axis direction so that it can be disposed together with the aperture unit in a plane orthogonal to the optical axis AX. Furthermore, the deceleration unit 63 and the aperture unit 66 are disposed at positions that partially overlap when viewed from the optical axis AX direction.

Thereby, even if the zoom motor 61 and the aperture unit 66 move relative to each other in the optical axis AX direction and overlap with each other when viewed from the direction orthogonal to the optical axis AX, mutual interference can be avoided. Therefore, the lens barrel 2 can be further downsized. Furthermore, the speed reduction unit 63 can be efficiently arranged in a space closer to the lens mount 71 than the diaphragm unit 66 on the inner circumference side than the outermost shape of the diaphragm unit 66 and on the outer circumference side of the third lens group G3. Therefore, the lens barrel 2 can be reduced in size.

Further, in the lens barrel 2 of the present embodiment, when not in use, as shown in FIG. 3, the inner rectilinear frame 41 is an end portion on the lens mount 71 side in the moving area W1 (an example of the moving area) in use. Is moved to a second position D2 further away from the first position D1 of the moving region W1 in use toward the lens mount 71 side.
The movement area W1 during use is such that, for example, when the lens barrel 2 is used, the inner rectilinear frame 41 moves in the optical axis direction with respect to the fixed frame 74 between the telephoto end photographing state and the wide end photographing state. It is a range. That is, when the lens barrel 2 is used, the inner rectilinear frame 41 moves in the optical axis direction with respect to the fixed frame 74 in the movement region W1 shown in FIG.

  In addition, the movement area W2 (movement area when not in use) shown in FIG. 3 is such that the inner rectilinear frame 41 is moved when the lens barrel 2 changes from the use state (non-use state) to the non-use state (use state). It is a moving area. As shown in FIG. 3, the movement area W2 when not in use corresponds to an area between the first position D1 and the second position D2. From this, when the lens barrel 2 is not used, the inner rectilinear frame 41 moves from the first position D1 to the second position D2.

3 shows an example in which the inner rectilinear frame 41 moves from the first position D1 to the second position D2 when the lens barrel 2 is not used. The rectilinear frame 41 may be disposed at the first position D1.
Thereby, a large amount of movement of the inner rectilinear frame 41 and the first lens group G1 can be secured. Therefore, it can be retracted when not in use, and can be miniaturized and highly convenient when carried. In addition, the first lens group G1 can be adapted to an optical system in which the first lens group is moved largely toward the subject side at the telephoto end. Therefore, the zoom ratio of the lens barrel 2 can be increased.

(Embodiment 2)
FIG. 10 is a cross-sectional view of the lens barrel 102 in the retracted state according to the second embodiment. Hereinafter, Embodiment 2 will be described with reference to FIG. In addition, about the structure which has the substantially same function as the structure of the said Embodiment 1, the same code | symbol is used and the detailed description is abbreviate | omitted.

In the configuration shown in FIG. 10, the second rectilinear key 142 of the inner rectilinear frame 141 is engaged with the second rectilinear guide groove 149 provided in the outer frame 170.
In this way, the second rectilinear key 142 provided on the inner rectilinear frame 141 is engaged with a member that does not rotate around the optical axis AX, that is, the rectilinear guide groove 149 provided on the outer frame 170, thereby causing the inner rectilinear advance. The rotation of the frame 141 around the optical axis AX can be restricted, and a small lens barrel can be realized as in the first embodiment.

(Embodiment 3)
FIG. 11 is a cross-sectional view of the lens barrel 202 in the retracted state according to the third embodiment. Hereinafter, Embodiment 3 will be described with reference to FIG. In addition, about the structure which has the substantially same function as the structure of the said Embodiment 1, the same code | symbol is used and the detailed description is abbreviate | omitted.

In the configuration shown in FIG. 11, the second rectilinear key 242 of the inner rectilinear frame 241 is engaged with the second rectilinear guide groove 249 provided in the outer rectilinear frame 246.
Thus, if the second rectilinear key 242 provided on the inner rectilinear frame 241 is engaged with a member that does not rotate around the optical axis AX, that is, the rectilinear guide groove 249 provided on the outer rectilinear frame 246, The rotation of the inner rectilinear frame 241 around the optical axis AX can be restricted, and a small lens barrel can be realized as in the first embodiment.

(Other embodiments)
As described above, Embodiments 1 to 3 have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to an embodiment in which changes, replacements, additions, omissions, and the like are appropriately performed. Moreover, it is also possible to combine each component demonstrated in the said Embodiment 1-3 and it can also be set as new embodiment.

Thus, hereinafter, other embodiments will be described together.
(1) In the above embodiment, the imaging apparatus 1 is described as an example, but the imaging apparatus is not limited to the imaging apparatus 1. For example, the imaging device 1 can perform still image shooting and moving image shooting, but the imaging device may be a device that performs only still image shooting or a device that performs only moving image shooting.
(2) In the above embodiment, the lens barrel is described by taking the lens barrel 2 as an example, but the lens barrel is not limited to the lens barrel 2. For example, the lens barrel may be a lens barrel used in an integrated imaging device instead of a replaceable lens barrel.
(3) Although the zoom motor 61 has been described as an example in the above embodiment, the zoom motor is not limited to a motor. Other types of actuators (for example, piezoelectric actuators) may be used as long as the arrangement in the longitudinal direction and the arrangement in the minimum dimension direction are the same as those in the first embodiment.
(4) In the above embodiment, the fixed frame 74 is attached to the outer frame 70, but may be attached to the lens mount 71.
(5) In the above embodiment, the cam frame gear 55 is provided on the lens mount 71 side and the second rectilinear key 42 is provided on the subject side. However, the cam frame gear 55 is provided on the subject side and the second rectilinear key 42 is provided on the subject side. It may be provided on the lens mount 71 side.
(6) In the above embodiment, the cam frame 50 and the outer frame 70 are engaged by the first cam pin 56 and the fifth cam groove 73, but the engagement configuration is not limited to this. For example, it may be engaged by a helicoid or the like.
(7) In the above-described embodiment, the rotation restriction of each member is realized by the engagement between the straight key and the straight guide groove, but the present invention is not limited to this. Other configurations may be used as long as rotation regulation can be realized.
(8) In the above embodiment, each of the focus lenses 29 is composed of one lens, but the present invention is not limited to this. Each may be composed of a plurality of lenses. Alternatively, the focus lens 29 may not be provided.
(9) In the above embodiment, there are three lens groups driven by the cam on the inner peripheral side of the cam frame 50, but the present invention is not limited to this. For example, only the second lens holding frame 15 and the third lens holding frame 17 may be provided, or four or more.
(10) In the above embodiment, the zoom operation and the focus operation are respectively operated by the zoom lever 77 and the focus lever 78, but are not limited thereto. Other operation units (for example, a zoom ring or a focus ring) may be used.
(11) In the above embodiment, the aperture unit 66 is attached to the subject side of the third lens group G3. However, the present invention is not limited to this. It may be attached to the lens mount 71 side of the third lens group G3.
(12) Although the aperture motor 68 is described as an example in the above embodiment, the aperture motor 68 is not limited to a motor. Other types of actuators (eg, solenoid actuators) may be used.
(13) In the above embodiment, the aperture motor 68 is provided closer to the lens mount 71 than the aperture blade 67, but the present invention is not limited to this. It may be provided closer to the subject than the aperture blade 67.
(14) In the above embodiment, each lens holding frame is provided with a cam pin, and the cam frame is provided with a cam groove. However, the present invention is not limited to this. For example, a cam groove may be provided in the lens holding frame, and a cam pin may be provided in the cam frame. Similarly, the bayonet groove and the bayonet key may be reversed and provided.
(15) In the above embodiment, the first lens holding frame 11 is composed of one component, but is not limited to this. For example, it may be composed of two parts, and may be divided into a cylindrical part having the second cam pin 12 and a lens holding part for holding the first lens group G1 and connected to each other.
(16) In the above embodiment, there are three cam pins, cam grooves, rectilinear keys, and rectilinear guide grooves, but the present invention is not limited to this. If the function is satisfied, the number may be less or more than three.
(17) In the above embodiment, the end surface of the cam frame 50 on the lens mount 71 side is flat, but the present invention is not limited to this. If there is a region protruding in the direction of the optical axis AX toward the lens mount 71 from the inner rectilinear frame 41, and the cam frame gear 55 is provided in the region, the end surface other than the cam frame gear 55 has a notch or the like. There may be.
(18) In the above embodiment, the gear train 64 is configured only by spur gear coupling, but is not limited thereto. Other gears such as a worm gear may be connected to a part.
(19) In the above embodiment, the zoom motor unit 60 is provided with all members other than the output gear 65 completely on the inner peripheral side of the inner rectilinear frame 41, but is not limited thereto. A part of the inner circumference side of the inner rectilinear frame 41 is thinned or cut away, and a part of the zoom motor 61 and a part of the speed reduction unit 63 enter the part, and partially overlap with the inner rectilinear frame 41 in the circumferential direction. It may be arranged at a position where

  Since the lens barrel of the present disclosure can be reduced in size, it is useful in the field of imaging devices. Specifically, the present disclosure is applicable to a digital still camera, a movie, a mobile phone with a camera function, a smartphone, and the like.

DESCRIPTION OF SYMBOLS 1 Imaging device 2 Lens barrel 3 Camera main body 4 Lens 11 1st lens holding frame 12 1st cam pin 13 1st rectilinear guide groove 14 1st rectilinear key 15 2nd lens holding frame 16 2nd cam pin 17 3rd lens holding frame 18 Third cam pin 19 Fourth lens holding frame 20 Fourth cam pin 28 Focus lens frame 29 Focus lens 35 Focus motor unit 36 Focus motor G1 First lens group G2 Second lens group G3 Third lens group G4 Fourth lens group 41 Inward straight traveling Frame 42 Second straight key 43a First bayonet groove 43b First bayonet key 44 First through groove 45 Second through groove 46 Outer straight frame 47 Third straight key 48a Second bayonet groove 48b Second bayonet key 49 Second straight guide Groove 50 Cam frame 51 First cam groove 52 Second cam groove 53 3rd cam groove 54 4th cam groove 55 Cam frame gear 56 1st cam pin 57 Cam frame convex part 60 Zoom motor unit 61 Zoom motor 62 Output shaft 63 Deceleration unit 64 Gear train 65 Output gear 66 Diaphragm unit 67 Diaphragm blade 68 Diaphragm motor 70 Outer frame 71 Lens mount 72 Third straight guide groove 73 Fifth cam groove 74 Fixed frame 75 Electrical board 76 Electrical contact unit 77 Zoom lever 78 Focus lever AX Optical axis

Claims (21)

A fixed frame,
A rotating frame engaged with the fixed frame via a cam pin or helicoid ;
A first rectilinear frame engaged with the rotating frame;
A first lens holding frame that holds a first lens group composed of at least one lens and is engaged with the rotating frame;
A first drive unit that is attached to the first rectilinear frame and that drives the rotary frame to rotate about an optical axis;
With
When the first drive unit and the first rectilinear frame move together in the optical axis direction relative to the fixed frame as the rotary frame is rotated by driving the first drive unit. At the same time, the first lens holding frame further moves in the optical axis direction relative to the relatively straight moving first frame.
Lens barrel. The first lens holding frame does not overlap the fixed frame when viewed from the direction perpendicular to the optical axis when moved to the most object side;
The lens barrel according to claim 1. The first drive unit is attached to an inner peripheral side of the first rectilinear frame.
The lens barrel according to claim 1. The rotating frame has a gear portion,
The first drive unit includes an actuator and a transmission mechanism,
The transmission mechanism engages with the gear portion and transmits the output of the actuator to the rotary frame.
The lens barrel according to claim 1. The ridge diameter of the gear portion is the same as the inner diameter of the first rectilinear frame or larger than the inner diameter of the first rectilinear frame.
The lens barrel according to claim 4. The longitudinal direction of the actuator is substantially parallel to the optical axis direction.
The lens barrel according to claim 4. The shortest dimension direction of the actuator is along the normal direction of the first rectilinear frame,
The lens barrel according to claim 4. One end of the rotating frame in the optical axis direction has a protrusion,
The protruding portion protrudes in the optical axis direction from the end portion of the first rectilinear frame with reference to an end portion of the first rectilinear frame,
The gear portion is provided on the protrusion.
The lens barrel according to claim 4. A second rectilinear frame that engages with the fixed frame, is restricted in rotation, engages with the rotary frame, and is supported so as to be movable in the optical axis direction while maintaining a constant distance from the rotary frame in the optical axis direction;
Further comprising
The first lens holding frame engages with the second rectilinear frame and is restricted from rotating.
The first rectilinear frame engages with any one of the first lens holding frame, the fixed frame, and the second rectilinear frame, and the rotation of the first rectilinear frame is restricted by the one of the frames.
The lens barrel according to claim 1. The protrusion is provided at an end on the opposite side of the subject in the optical axis direction of the rotary frame.
The lens barrel according to claim 8. The rotating frame has a gear portion,
The first rectilinear frame is provided on the inner peripheral side of the rotary frame, and is engaged with the first lens holding frame at the end of the rotary frame on the side far from the gear portion, and the rotation is restricted.
The lens barrel according to claim 9. The first lens holding frame is provided on the outer peripheral side of the rotating frame, and has at least one of one or more first cam pins and first cam grooves on the inner peripheral side,
The rotating frame has at least one of the first cam pin and the first cam groove on the outer peripheral side,
The first cam pin and the first cam groove are engaged,
The second rectilinear frame is provided on the outer peripheral side of the first lens holding frame.
The lens barrel according to claim 9. A second lens holding frame that is disposed on the inner peripheral side of the first rectilinear frame and has a second cam pin that penetrates the first rectilinear frame from the inner peripheral side to the outer peripheral side and engages with the rotating frame;
Further comprising
The rotating frame has a second cam groove that engages with the second cam pin on an inner peripheral side,
The second lens holding frame is restricted in rotation by engagement with the first rectilinear frame, and is driven in the optical axis direction by a rotation operation of the rotary frame.
The lens barrel according to claim 1. The second lens holding frame holds a second lens group composed of at least one lens,
The second lens group is provided on a side farther from the subject than the first lens group.
The lens barrel according to claim 13. A third lens holding frame that is disposed on the inner peripheral side of the first rectilinear frame and has a third cam pin that penetrates the first rectilinear frame from the inner peripheral side to the outer peripheral side and engages with the rotating frame;
Further comprising
The rotating frame has a third cam groove that engages with the third cam pin on an inner peripheral side,
The third lens holding frame is rotationally restricted by engagement with the first rectilinear frame, and is driven in the optical axis direction by the rotation operation of the rotating frame,
When viewed from the optical axis direction, the actuator is disposed between the second cam pin and the third cam pin.
The lens barrel according to claim 13. The first drive unit has a transmission mechanism that transmits the output of the actuator to the rotary frame;
When viewed from the optical axis direction, at least one of the second cam pin and the third cam pin overlaps the transmission mechanism.
The lens barrel according to claim 15. A fourth lens holding frame supported so as to be relatively movable in the optical axis direction with respect to the second lens holding frame;
A second drive unit for driving the fourth lens holding frame in the optical axis direction;
Further comprising
When viewed from the optical axis direction, the second drive unit is disposed between the second cam pin and the third cam pin.
The lens barrel according to claim 15. Between the first drive unit and the second drive unit, at least one of the second cam pin and the third cam pin is disposed.
The lens barrel according to claim 15. An electric board for supplying electricity to the first driving unit;
Further comprising
The electrical board is attached to the fixed frame;
In a state where the first rectilinear frame is closest to the electric board, the first driving unit and the electric board are arranged in a plane perpendicular to the optical axis.
The lens barrel according to claim 1. An aperture unit that is arranged so as to be movable in the optical axis direction with respect to the fixed frame and adjusts the amount of light taken from the subject,
Further comprising
The first drive unit has an actuator,
The actuator is movable in the optical axis direction so that it can be arranged with the diaphragm unit in a plane orthogonal to the optical axis.
The lens barrel according to claim 1. When not in use, the same first position as the first end on the side farther from the subject in the moving area that moves in the optical axis direction with respect to the fixed frame, or the farther from the first end with respect to the subject. The first rectilinear frame moves to position 2,
The lens barrel according to claim 1.

Images